Metal sawing machine



Dec. 10, 1946. A. ZlSKA METAL SAWING MACHINE Filed Au 6, 1943 '7 Shee ts-Sheet l INVENTOR. 1905/ Z/S/f/i /4 "2 a /5 I i f .2.

PKG a. w \NXQQQQ Dec. 10, 1946. A. ZISKA- I METAL SAWING MACHINE 7 Sheets-Sheet 2 Filed Aug. 6; 1943 1 w. widghsl BS/(NA 7'7'0/E/VEH I Dec, 10, 19%, A. ZISKA METAL SAWING MACHINE I Filed Aug. 6, 1945 7 Sheets-Sheet '3 g w x HTTOEN EY. i

Dec. 10, 1946. A. ZISKA METAL SAWING MACHINE Filed Aug. 6, 1945 '7 Sheets-Sheet 4 INVENTOR. 1906/ wig f HTTOE/VE? BY wk) A. ZISKA METAL SAWING MACHINE Dec. 10, 1946.

Filed Aug. 6 1945 IrJ.-J LJ 7 Sheets-Sheet 5 Dec. 10, 1946. I ,1 z s 2,412,311

METAL SAWING MACHINE Filed Aug. 6, 1943 7 Sheets-Shet 6 IN VENTOR. flDfi/V Z [15% A BY \lo ATTORNEY Dec. 10, 1946. A. ZISKA METAL SAWING' MACHINE Filed 'Aug. 6, 1943 7 Sheets-Sheet 7 CYAQINDE/B /6.6 on w 4-way HTTOENEK Patented Dec. 10, 1946 NT OFFICE METAL SAWING MACHINE Adam Ziska, Wauwatosa, Wis., assignor to Peerless Machine Company, Racine, Wis., a corporation of Wisconsin Application August 6, 1943, Se rial No. 497,568

23 Claims. 1

' This invention relates to improvements in power-operated metal hack saw machines which while capable of embodiment, with singular advantages, in the duplex type of metal sawing machine, also incorporates in its construction various novel features susceptible of advantageous use in metal sawing machines where only a single saw is used.

One of the objects of the invention is to constitute and organize a machine of this character that is strong, rugged, and durable in construction, eflicient and rapid in operation, and so controlled in its action that each sawing cycle is largely automatically governed although provision is made for manual control at all times.

Another object of the invention is to so constitute a machine of this character and having the advantages mentioned in that it provides a unitary, self-contained construction in which the fluid'pressure motors that reciprocate the feed and saw frames are completely enclosed and yet are closely and compactly as well as effectively organized with the parts with which they are interconnected. The pumps which supply the fluid under pressure to the. fluid pressure motors are also housed and carried by the feed frame, and the electric motor which drives both pumps is carried by the feed frame though disposed exteriorly thereof. The necessity of resorting to flexible or telescopic connections between the pumps and the fluid pressure motors is avoided.

Another object of the invention is to provide an improved feed and saw frame construction and or anization operable to advantage for sin le sawing or for duplex sawing when two sets of saw and feed frames are ope'ratively interrelated.

A further object of the invention is to provide novel and advantageous means fortensioning the saw and its backing plate and for controlling the irliterengagement between the saw and its backing p ate.

Other objects and advantages reside in certain novel features of the construction, arrangement, and combination of parts, which will be hereinafter more fully described and particularly pointed outin the appended claims, reference bein had to the accompanying drawings forming a part of this specification, and in which:

Figure l is a view in side elevation illustrating a duplex metal hack saw machine embodying the present invention;

Figure 2 is a fragmentary view partly in side elevation but mainly in longitudinal, vertical cross section, illustrating the fluid pressure motor employed to reciprocate each feed frame and also the motor and pump which provide the fluid pressure medium for actuating themotor;

Figure 3 is a View in endelevation of the metal hack saw machine illustrated in Figures 1 and. 2; Figure 4 is a fragmentary View in top plan of the metal hack saw machine illustrated in Figures lto 3;

Figure 5 is a View partly in top plan and partly in, transverse, horizontal cross" section, illustrating the structure of onejof the feed frames and of its associated saw frame, a view being taken on line 5'-5 of Figure 6; l

Figure 6 is a fragmentary View, partly in side elevation and partly in longitudinal, vertical cross section, taken on line G6 of Figure 5;

Figure 'Tis a View in vertical, transverse cross section taken on line 'l-'l of Figure 8;

Figure 8 is a fragmentary view partlyin top plan and partly in longitudinal, horizontal cross section, illustrating the slip clutches employed to protect the tensioning means for the saw blade and the backing plate and also the eccentric gear utilized to control the operative relationship between the'backing plate and the saw blade;

Figure 9 is a detail View in side elevation showing the structure of the eccentric gear employed to control the operative relationship between the backing plate and the saw blade;

Figure 10 is a view in vertical cross section,-

takenon line Ill-4i! of Figure 8, with parts shown in elevation for the sake of illustration; t

Figure 11 is afragmentary view on an enlarged scale, and in side elevation, tobetter illustrate the manner in which the saw blade and the backing plate are combined with the saw frame and controlled as to position and tension; v

Figure 12 is a fragmentary View partly in side elevation and partly in cross section and diagrammatically illustrating the valves which take part in the control of the sawing and return strokes of the saw frame andthe feeding and withdrawal strokes of the feed frame, and also illustrating the cams and the trip fingers combined with the saw frame and valves and employed for the pur- I pose of automatically operating the valves;

Figure 13 is a view taken on line l3-l3 of Figure 12 and further illustrating the cams and trip fingers shown in Figure 12; I

Figure 14 is a detail View in side elevation of one of the feed frames; z V Figure 15 is a view in vertical cross section taken on lines l5-l5 of Figure 14;

Figure 16 is a detail view in top plan of one of the saw frames;

Figure 17 is a detail viewin side elevation of 5 one of the saw frames;

Figure 18 is a detail view in diametrical cross 1 section showing the valve mechanism employed to Figure 20 is a diagram of .the hydraulic circuits 1 operemployed to control various phases of the ating cycles of the machine; and

Figure 21 is a detail view in top plan-of one of the tracks or ways provided on the 'base for cooperation with a feed frame.

Referring to the drawings, and more particusuitably house the motor-driven pump which sup-v plies the fluid under pressure to said motor.

As illustrated in Figures 2, 14, 15, and 21 the central portion of the bottom wall of the base 5 1 is provided with a raised portion 8 formed with downwardly opening recess which overlies an elongated longitudinal slot 9 providedin each undercut guide rail 1 and sasimilar and registering elongated slot lfl'providedin-the top wall of larly to Figures 1, 3, and 4,-it will be seen that the duplex metal hack saw machine embodying,"

the present invention generally comprises a base A which may be a metal casting supported on a suitable foundation. Fitted to guiding ways in the base ,A, for sliding horizontal .movementwith respect thereto are a pair of similar feed frames,

designated generally .at F1 and F2. 'Thes'e'feed f frames F1, F2 are of identical construction, but are oppositely disposed. Combined with each feed frame is a vertically reciprocal saw frame ing plate P. Supported on the base on the opposite sides of the feedframes are the work tables, W1 designating the front work table. equipped with suitable gauges 1G, and W2 designating. the rear work table, which is slotted and equipped with suitable fixtures to maintain the work in position for sawing. The confronting edges of S. .Mounted on each saw. frame S, and tensioned and positioned .in a manner to. be hereinafter more fully described, is a saw blade B and back- 1 the work tables are suitably spaced to provide 1 clearance for the saw blade B and backing plate P. I

. The base A is of hollow construction, and. its main longitudinal portion, on which the feed frames F1- and F2 are mounted, is provided with parallel, undercut, longitudinal ways, designated at l. These ways, which are of baror rail-like form, are of similar construction and are shown in end elevation in Figure 3 and indetail-in Figure 21. They are securely fixed to; the horizontal top portion'of the base by means of counter sunk screws, bolts, or other fastening devices, and they are designed-and proportioned to slidably interfit with similarly formed guide grooves 3 1 machined on the undersides or bottoms of the feed frames F1 and F2 (see Figures 3 and 15). Suitable gibs 4 are combined with this interconnecting and guiding structure to take up wear and provide for adjustment. 1 7

As indicated, the feed frames F1 and F2 are of identical construction although oppositely -ar ranged. They are shown in detail in Figures 14 and 15. Each feed frame is generally of rec- 1 tangular construction and includes a hollowhori- Zontal base section 5 and hollow .and vertically disposed. uprights or standards 6, which have their lower ends integral with the outer ends of 1 the base section 5; and-are disposed parallel to 1 each other.

each feed frame is dithe base A under each slot 9.

' The fluid pressure motor, which drives each feed frame, has its cylinder ,H disposed in the recess 8 and slots 9 and IE3. Each cylinder H I issecurely fixed to the wall of the raised portion -8 and oonsequently'is fixed to and moves with its feed frame. I A piston I2 is slidably fitted in each cylinder and ,has a piston rod [3 projecting through a stuillng box [4 provided at one end of eachcylinder ll. The outer end of each piston rod I3 is anchored to its associated guide rail I, and consequently to the base A. For thispur pose,1each guide rail 1 is.p 1 .ovidedwitha vertical hole 15 therethrough and disposedad-J'acent :to though spaced from one end of the ;slot 9 thereof. The portion 2 of each guide raili, located .between its hole i 5 and theadjacent endofgitsslot 9, is formed with. a lengthwise hole 2' whose axis is coincident with the longitudinal axis of the guide rail I... The outer end of each iston rod I 3 is reduced and shouldered and interfitted with r the holefl of portion 2' .of its rail 1. A inut t5", threaded on the extreme outerendof each piston rod 1 3, coacts with-the portionZ rod to 'itsfguide rail 1. 1

The fluid pressure medium, which is alternately supplied to the opposite ends of the cylinder :9, is derived from a pump 16, which may be of;-any

suitable type and which is mounted on a supporting bracket 16' fixed to one end of the base 15 of the feed frame. To thesame end wall oft-he. base 5 of each feed frame is secured-an electric feed frame is of the self-contained typeia-nd is directly connected thereto and carried thereby. Any necessity of resorting to flexible or telescopic connections is avoided.

Each saw frame S is of square constructiongas illustrated to advantage in Figures 1, 6, and Y17;

Each such saw frame is made up of upper and lowercross members, designated at 2'5 and -2$,"in-

" terconnected at their ends with vertical side mem bers 21 and 28, these parts being'combined into one unitary structure-by welding or by other appropriate means of securing "them together. Welding, however, is preferred.

The side members 27 and 23 of thesaw framehave their outer portions of V shape in horizontal cross-section to. provide slides 29 and33fi which slidably interfit with correspondingly; formed guide grooves ti and 32 (see Fig-.- 5) formedin guide rails 33 and '34, bolted or otherwise suitably fixed to the confronting or inner walls of the vertically disposed uprights or standards of the o. x s c oist n feed frame (see especially Figures 5, 6, 16, and 17).. The center line of the slide 29 is offset from the center line of the slide 30 on each saw frame to permit the two saws to operate in the same sawing planewhile minimizing the moment arm between the application of the sawing force to thesaw and its absorption by the saw frame. This is accomplished as shown in Figures 5 and 16 by making the upper cross member 26 of each saw frame of the offset construction illustrated and correspondingly forming each lower cross member 25.

, Each saw blade B is anchored at its lower end to the lower cross member 25 of its saw frame by means of a lower saw grip which comprises a short rectangular bar provided with a transverse slot 36 in which the lower end of the saw blade is fitted and to which it is secured by dowel pin 38 (see Figures 7 and 11) and in which it is clamped by virtue of the action of a clamp S re 31. Each lower saw grip or anchor 35 is fitted in a groove provided therefor in the lower cross member 25 of its saw frame and is securely held in position by dowel pin 40 and stud bolt 4|. The upper end of each saw blade is also interfitted with the slot 42 provided in the lowerend of an adjustable upper saw grip 43 and is fastened to this upper saw grip by dowel pin 44 and clamp screw 45 as before. The upper saw grip is barlike in construction but elongated, and a portion of its rear face is provided with rack teeth or worm teeth 46. The upper saw grip has tapering side edges to adapt it to slide in an undercut guide groove 41 provided in the upper cross member 26 of the saw frame. The top of the upper cross member of the saw frame, just in back of the guide 41, is formed with a bearing socket 49 to receive a driving worm 50. The worm 50 meshes with the teeth 46 of the adjustable upper saw grip. It has projecting from its lower side,

and coaxially disposed with it, a mounting shaft upper saw grip will be moved upwardly and tensioning applied to the saw blade, whereas when it is moved in the opposite direction the upper saw grip will move downwardly and will reduce or relieve the tension. To facilitate turning of the worm 50, and also prevent overstressing of the parts, its squared tool-engaging stud is not rigidly connected to it but rather is connected to it through a slip clutch designated generally at 56. This slip clutch comprises a hub 51 formed integral with the tool-engaging stud 55 and fitted for rotation in a correspondingly formed cavity provided therefor in the center of the worm. Spring-projected balls 58, carried by the hub and normally interlocked with semi-spherical cavities 59, are provided in the socket in. the worm. When, however, an excessive force is placed on the parts, the springs yield, theballs slip outof the recesses, and the stud 55 turns without any appreciable torque being transmitted to the worm.

Each backin plate P is also anchored to the lowerv member 25 of its saw frame with respect of any vertical movement although it may be shifted horizontally. For this purpose (see Figs. 10 and 11) a lower plate anchor in the form of a reccross member of its saw frame and is securely fastenediin position inthis groove by countersunk stud bolts 6|. Each lower plate anchor has integrally formed therewith an outwardly/projecting and downwardly acting hook'or grab. 62', the bill or active portion of which is undercut. The ends of the backing plate P are of thickened construction as they. are reinforced by reinforcing plates welded thereto andin effect integral there with. f The design 'issuch that the ends-of the backing plate are of the same'thick-ness as the saw' grips. A slot 64 is formedin :the lower end of the backing plate and has its lower wall 63 angledor slanted toeffectively engage andfcooperate with the undercut surface of the'bi'llof the hook 62, which inithe assembly is received'in the slot 64. The slot 64 and hook or bill 62 are so dimensioned and proportioned that while the backing plate may not move vertically with respect to the hookor bill, it may slide horizontally with respect thereto. a

An adjustable upper plate anchor 65 is provided and is slidablyinterfitted within a vertical, undercut guide slot 65' provided therefor in the upper cross member of the saw frame. Thisupper plate anchor is provided with an upwardly facing bill or hook 66 which coacts with the slot 51 provided in the upper end portion of the back ing plate and is effective to control the tension of the backing plate while leaving it free to shift horizontally. For moving the upper plate anchor upand down, and thus controlling the tension of the backing plate, a worm 69 is combined with the upper cross bar of the saw frame in the same manner as the, worm 50 and interengages' with Worm teeth Til on the back of the adjustable up per plate anchor. The. worm 69 may be 'actu ated from a tool-engaging stud 1 I ,operatively interrelated with the worm through a slip clutch '52 as before. A cover plate 13 retains the slip clutches in the-cavities of their worms. I

In addition to this mechanism for controlling the tension of the backing plate, means is provided to shift it horizontally-that is, toward and away from the saw blade. This means includes upper and lower clips l5 riveted or otherwise suitably secured to the backing plate and havin theirinturned ends "embracing adjusting blocks 18. These blocks 78 are mounted on eccentric pins 19 fixed to shafts 80 rotatably mounted in the crossmembers of the saw frame and controlled as to adjustments by means of adjusting plates 8| which have a segmental slot 82 therein adapted to coast with clamping nut and bolts 83 whereby the adjusting plate'may be held in any adjustment. l

Each saw frame is reciprocated vertically by means of a pair of fiuidpressure motors, designated at 85 and 85, disposed on the opposite sides of the saw frame. The motors 85 and 86 are of identical construction and are enclosed in the hollow uprights or standards 6 of the feed frames. The cylinder 81 of each motor is fixed to its feed frame and this may be accomplished by means of the same bolts designated at 81', which fix 6). A piston 38 is fitted in each cylinder 81 and has a pistonrod 89 fixed thereto and projecting exteriorly through a suitable packing gland at the lower end'of the cylinder. The lower end of each piston rod is fixed to a driving arm 90 which is interfitted with notches 90 formed in the slides of the saw frame and secured bolts 9 I.

7 ticalzzslots provided therefor: in the. uprights or standards ii of the feed frames and in the guide rails 33.. Obviously as the pistons 88 reciprocate in their cylinder 81, the driving arms moving vertically in the slots will reciprocate the saw frames. e The saw. frames S have a. substantial vertical stroke,- in the particular machine shown a. vertical stroke of six inches, The machine as viewed in Figure 1 would appear not to provide the clearance necessary forsuch a stroke but that such clearance .is available may readily be realized uponinspection of Figure which "illustrates that'the feedframes are pocketed as at 6 to allow the; saw frame to descend as required. Also the upper cross member 7 of .each feed frame is formed with a vertical opening 92 to provide for convenient access to the tool-engaging studs and TI. I .The hydraulic circuit which regulates theaction of the fluid pressure motor which drives each feed frame, hereinafter called feed motor, and the fluid pressure motors which drive each saw frame, hereinafter called saw motor, is illustrated diagrammatically in. Figure 20. There is one such circuit for each feed and saw frame assembly. In each of these hydraulic circuits the pump I6 has its discharge port connected .by conduit 93' to the intake port 94 of a control valve designated generally'at 95. Y

The control valves 95 function, in one. of their positions, and in conjunction with the other instrumentalities of the hydraulic circuits, to cause continuous and automatic repetition of the operations which comprise the sawing cycles; namely, downward movement of both saw frames S and-both saws B on each sawing stroke, simultaneous feeding movement of both feed frames 'FI, F2, and of both saws B into the work'on each sawing stroke, upward or return movement of both saw frames S and both saws B at the 8 .The distributing or reversing. valve 91 andith pilot valve 98 are-synchronized in their action with the vertical movements of their saw'frame S. In the construction shown in Figure'ZO these valves 9'! and 98 are illustrated as having a common plunger or valve pistouIIi'S-connected by a lost motion connection to one 'of the'piston rods of one of the saw motors as illustrated diagram: matically in Figure; 20. Such lost'motion con nection includes an arm 89" fixed on the iston rod 89 of one of the saw frame actuatingmotors 81 and formed with a hole through the'ext'ended end thereofl The stem lilt of thevalve piston its extends through the hole in the arm 89 and is freely slidabl'e' therein within" thelimits' 'imposed by collars i9 1 and Ifid' fixed' on such "valve stem. j j Figures 12 and 13 diagrammatically illustrate that rotary valve'means designated at 96a and 99a may be employedin lieu of the valve means, 96 and 39, respectively, of Figure 20. When 1 versing valve 99 are shown as being'piston'valv'es;

This, or course, is for the sake of illustration; Obviously, rotary valves or other suitable types of'valves might be employed.

However, in the construction'shown, the control valve 95 has a valve casing -or' valve body E95 preferably of cylindrical form. Opposite or angularly spaced from its intake port 94; are two outlet ports I96 and I97, these ports being located symmetrically with respect to the intake port 94 completion of each sawing stroke, and limited retraction or withdrawal of both feed frames Fl F2, and both saws B simultaneously with their upward or return movement.

In. the other position of the valves 95 they function to cause complete return of the feed frames FI, F2, and saws B to starting position.

Each control valve95 is interconnected in a special Way with valve means 96. The valve means 96 is in reality two valves, combined intoone, for the sake of convenience and simplicity of structure. The lower portion 91 thereof functions as. a distributing 0r reversing valve for the feed motor with which it is associated while the upper portion 98 thereof is a pilot valve to regulate the action of a reversing or distributing valve 99 employed for the purpose of controlling the operation of its pair .of saw motors 85 and 86.

Of course'the distributing or reversin valve 9'! and the pilot valve 98 could be separate valve structures.

The control valve 95 ispreferably electromag netically controlled and for thispurpose it may have solenoid I03 combined with its valve plunger or piston Ifll. vWhen the solenoid is energized it raises the valve piston Mil and-so positions the valve as to provide. for the automatic repetition of theoperations'which com prise the sawing cycles. .When the solenoid is deenergized the valve piston IOI, underthe influence of suitable biasing means, such as a coil spring 922, is shifted to its other position wherein it effects-complete return, as will be hereinafter more fully described.

in a direction lengthwise of the valve body. Axially spaced from the ports ass and I0? and on the same side of the valve are returnports I08 and I99. On the opposite sideof the valve from the outlet and return portsand axially spaced from the intake port 9 5 are discharge] ports HE! and Ill. The piston or plunger IflI of the con-- trol valve is provided with a piston headfI ['2 which in the position shown inFigure 20 blocks connnunication between the intake port fltfand the outlet port IIlI, but establishes communication between this intake port 94 and the outlet port I 96. Any communication between the intake port 94 and the return ports IE8 and I09 is blocked by'piston heads H3 and I I2 suitably mag chined onthe piston of the valve. 7 j j 1 Communication betweenthe return ports I 09 and H39 and the discharge ports llfl'and I! I'is under the control of piston heads H3 and Hit provided on the piston of the valve.

The distributing or reversing valve 9'! and the 7' pilot valve 99 have, 'in the constructionillus trated, a common valve body H! which also may be of cylindrical form. The distributing o'rjre versing valve section. 91 of tthis common valve' body is provided on one side 'withiports H8, H9 and I29; and on its opposite sidejwith' ports' ll2'l.. and I22; .Notonly does this valve means 96 which is comprehensive of the two valvesnamed;have

a common valve body, but it also has the common 1 valve piston or plunger 5 B3. The lower sectionof this piston or plunger I03 which functio'nsaslan element of the distributing or reversing valve is provided with piston heads designated at I23, I24 and I25. The upper or pilot section 980i the valve body II! is rovided on one side with ports I29, I21 and I28, and on its opposite sides" with-ports I29 and I30. The upper section of the piston or plunger serving the pilot valve 98 isyprovided ;with';piston heads =I3I, I32 and I33. Intermediate the distributing or reversing section 91 of the valve means 96 and its pilot section 98- the common plunger I03 of the valve is provided with a blocking and guiding piston head I34 which is a working fit in the intermediate portion of the valve body. 1

The feedport I06 of the control valve is connected by a pipe or= conduit I35 to the port H6 of the distributing or-reversing valve 91. This port I I9 of the distributing or reversing valve 97 alternately communicates with the ports I2 I and I22, communication between the port H9; and the port I2I occurring whenuthesaw frame is at the .top ofits, stroke. As the saw frame descends, this communication between ports H9 and I2I is blocked and as the saw frame reaches the lower end of its stroke'the piston head I24 moves downwardlyf'to provide forv communication between the port IIQ-andtheport I22. The port I2I connects by means of a pipeor conduitl36 with a feed pressure control-I31 of standard constructiornand also with the gauge I38. A branch conduit I39 in open--communication with the conduit I36 connects'to a stroke limiting device I40,'the latter in turn connecting through a pipe or conduit [4! with .one end of'the feed cylinder EI. The, stroke limiting device I40 is identical With that described and claimed in United States Letters Patent No. 2,202,256, granted May 28, 1940, to .0. M. Jensen et al, for Hydraulic feed for; powersdriven hack saws, and comprises in general'a cylinder I40a and a piston I451) (see Figure '18), the -piston I40ba.being of limited stroke and having a checkgvalve I400 therein which permitsthe free flow of the fiuid pressure through they-piston I401) in one direction, but blocks all flow through the piston. I40b in the opposite direction'. 'I-Ioweven' when the pressure is exerted against the check valve I400, the piston may move a'limite'ddistan'ce'and consequently permit a limited displacement of 'the fluid under pressure. The function of this device is to allow the full force of the hydraulic pressure to feed the saws into the work, butto limit the extent of their withdrawal or retraction on each return stroke. Withthe valves in theiposition' described, the fluid under pressure is supplied to the left-hand end of'the feed cylinder II, as viewed in Figure 20, and the cylinder II is driven with respect to its piston I2 to feedits'saw into the work. At thesame time fluid is exhausted from the opposite endof' the cylinder, since it flows through conduitor pipeline 142 toport I22 of valve 91, thence across the valve to port I20, through pipe. lines I43 and I44; to the return por-t I09, through the valve95, to the discharge port III, and then through pipe lines I45 and I46, back tothe sump or oil reservoir. 7

At the completion of the'sawing stroke, the valve plunger I03 has moved downwardly from the position shown inFigure to the lower limit of its stroke, so that the circulation or distribution of the fluid under pressure is reversed;:for lat'suchtime the fluid pressure flows from. the port I06 ofthe control valve through the pipe line or conduit I35, port 9, as before,

10 '20, but for a limited distance only, since it can only move as far as the piston l llib of the stroke limiting. device I40 will allow it. There is, however,-a limitedmovement sufficient for adequate withdrawal or retraction of the saw from its workduring its return stroke. The fluid under pressure displaced by the stroke limiting device I 40 moves back through conduits I39 and I36; to port I2I, them across to port H6, and from port I I8 through conduits Hi8 and I44, to return port; I69, then across to discharge port III and back through the pipes I45. and I46 to the sump. During the time that the feed cylinder II is feeding its feed frame and consequently the saw into the work, the saw frame is being driven downwardly through its sawing stroke by means of th fluid pressure motors 85 and 86.1 On the other hand, when the feed cylinder is actuated to withdraw or retract, the feed frames and consequently the saws from the work, the saw frames are being moved upwardly bythe motors 85 and 86 on their return stroke. The motors. 85 and 86; are servedby a separate pump designated at I50 supported with the pump I6, on the bracket I6 and like the pump I6 driven by the electric motor H. The discharge port of the pump connects to aflow'controland relief valve I5I of conventional construction, which in turn has a pipe line I52 leading'therefrom. A gauge I53 may be tappedinto pipe line I52. A conduit I53 leads -from ,thepipe line I52 to the intake por-t I54 of the four-way valve 99 which controls th distribution of the fluid pressure to the motors 85 and 86. This valve 99 is of conventional construction and is shown diagrammatically as having a cylindrical valve body I55. On the same side of the valve bodyasthe intake port I54, are exhaust ports I56 and I5'Iwhich lead-back to the oil sump or reservoir. On the opposite side of-the valve: body from the ports I54, I56 and I5'IYare, outlet ports I58 and I59. Conduit-.160 leads from the outlet port I58 and has branches I61 and I 62 leading. to thelower ends of the cyIindersB'Iof -thefluid pressure motors 85and- 86. Similarly, a conduit I63 leads from the:out-: let port ,I59 and has branches I64 and I65 communicating with the upper ends of the ylinders 81 ofthe motors-95 and 86. The valve proper is in theform of a piston. I66 shiftable lengthwise in the valve body and, having three piston heads serving in one position of the piston to supply fiuidunder pressure to the upper ends of the cylinders 81 of the motors 85 and 86, while at the same time exhausting fluid under pressure from the lower ends of such cylinders. In the other position of the piston I66 the action is reversed and fluid under pressure is supplied to the lowerends of the cylinders 81 of the motors 05 and 86 while it is exhausted from the upper ends thereof. This piston valve I66 is automatically shifted, and shifted in synchronism with the other operations by the pilot'valve 98. For thispurpose one end of the valvebody'I55 is connected by pipeline .161. to the port I29 01", the pilot valve, Whereas the opposite end of thebody is connected'by pipeline I68 to the port I30 of the pilot valve. The'intake port I2I 0f the pilot valve is connected to the conduit I52 and consequently receives the pump pressure. The ports I26 and H6 of the pilot valve are connected by. pipe lines I69 and H0 to the oil reservoiror "sump. f I

With this construction when the piston of the pilot valve 98 is in the position-shown in Figure 20, fluidiunder pressure flows through the pipe I63 and its branches I 64 and I65'to the upper' end of the cylinders 81 or the motors 85 and $6. The sawing stroke ensues: A t-the same time the fluid under pressure is exhausted from the lower ends of the" cylinders- 81' of the motors 85 and: 86 through the pipeline I66 and its branches I B l-"and I62,- to port I58,and across the valve to --the exhaust port I56.

Upori the completion of thes'awingstroke the pilot'valve is shifted downwardly so asto block cdrhmuhibation between the intake port I27 and C ifit'l'e'tf port I2 9, while establishing communicati'r'i between the inlet port I27 and the outlet hen I3El When this occui 's' fluid under pressure fidws fro'iii' the-outlet port 130 through the pipe or eoh'duit I63 to the left-hand end of the valve bed" F55; 'Valv e piston IE6 is then-shifted to the ight with the result that fluid under pressure is" supplied to the lower ends of the cylinders 81 of the'ino'tors; 85 and BB and exhausted from theup per' ends of these cylihde'rs; a

when the solenoid I03 is deenergized and the pistes of, valve 95 drops'to' its lower position, the valve'ineans- 96 is bypassed and a hydraulic circL-ii is e'stfablislhedato the feed motor through the control valve 95 te cause the feed motor to effect eempieteiethr'h of the feed'frame, thatis' a full return tdstarting position; At such time fluid under pressure-n ws from-'iritake po'rt9'4 of valve as acrbss-t'o outlet port 101 and then thro'ugh a Iii l d lili IJ'H} tqpipe line! and into the righthand end: of cylinder H as viewed in Figure 20'. Fluid" pres'siire is exhausted from the opposite end of cylinder. I! through pipe Mite pipe I12;- Pipe l-riz 1eadteport-ms which'i'n-lower positidh o control valve 95 is'ificommunication with'dis-F' charge" port. I I 0. Port II I]- eemmuhiee-tes' through pipe J13 with pipe I46 leading back tosump;-

j electric CilCllilS- the 1 11101161 l1 "WhiCh' drives'the' pumps combined with each'feed frame is showh'iii diagram in- Figure 19. There'is nt-hing! s'peciah'about the circuit itself; Any standard circuitu'nay be employed. It is desirable to'in corporate in the circuit a starting switch I16; a stepping switch I11 and areversing switch H8 In additioma left-hand and a right-hand microswi-tchidesignated atI'I9 and [80; respectively, are incorporated in the circuit. These switches I79 and 1 85 are preferably incorporatedin a single housing ls-I ,(see Fig. 1) fixe'd to the lower portion ofthe feed frame and their operating pluhgers coactwith adjustable trip cams I82 and I83. The cams: I8,,2;and I'83' are adjustable along a [slottedguide; i84 carried by the base oi the machine; The guide ta l may be provided witha sealel85 to facilitate precision Y adjustment of the trip cams; "The trip cams I82 and I83 maybe adjusted' tov cause the sawing to start at any selected startingipoint' and proceed to any other selected stopping point within the'range of action of the machine, and when the sawing has progressed to the stopping pQl'ntthe trip cam I82 acting on micro-switch I18 reverses the actionfan'd causes the feed frame to return automatically to its ih l i pfl i While theinvention is capable of advantageous embodiment ina' duplex type ofsawingmachine;

litigant 7 i2 a es -mush man of its features may be em eyea' to advantage where-only a single sawis used.

Insuch a case thee-won er-e;euise een V ohe-fejed-irar heand one saw fra e.--

While I have shown and described one 00 structionin which the invention may be have-h ,tageously embodieddt is to be understood I the construction shown has been selectedi'merelyfor the purpose of illustration{M -example,"and that various changes in the size, shape, and arrangement of the parts may be made without dparting from the 'spirit'ef'theinvention d scope of the subjoined claims Iclaimz 7 1'.= A metal sawin machme comprisinga hbllw base, a feed-frame having hollow Vertical side" members and upper and lower" cross 'me'mbefs connecting said side members,interfitting guidingways between the lowercross member and the base to constrain the feedframe to horizontal rei-i ciprocatory movement, a fluid pressure motor within the confines of the hollow base'andinter-f connected with the base and'the lower-cross member-for reciprocating the feed frame, as'aw frame interfitted with guiding ways on the ver- V r tical side members and-constrained to vertical" reciprocatory movement, "and fluid pressure mo tors housed in the hollow vertical side members and interconnecting the side members and the sawframe' for reciprocating the saw frame,

'2. A 'metal sawing machine comprising a. base,

a feed frame interfittedwith guiding ways on the base for reciprocatory movement, said feed frame having hollow side membersga saw frame inter V V fitted with guiding ways on the side members forreciprocatory inovefnent relative to the feed frame, a saw blade fixed to the saw frame, fluid pressure motors for reciprocating the saw frame, I

saidmotors being housed in the hollow sidemem bers. and "including cylinders fixed to the side members and pistons voperatively connected thesaw frame. g v A metal sawing machine comprising a stationary frame, a feed frame fitted to guiding ways j on the stationary frame, said feed frame comprisin'g cross members and hollow aside members connected. to thercross members, guiding rails fixed to the side members of the feed frame and hava ing confronting V-shaped guide grooves, a saw frame including cross members and side mem'-' bers connecting said cross members, the} side members of'the-sawframe being formed/with J-shaped slides interfitted .with the Veshaped guidegrooves of the guide rails, the hollow meme bersof the vfeed frame and the guide rails having registering slotsga pair of fluid pressure motors for reciprocatingthesaW frame, saidmotors being disposed in the hollow members of the feed frameand having'cylinders fixed to said hollow side members of the feed frame, pistons fitted inv the cylinders and having piston rodsprojecting exteriorly thereof, and driving arms securedto the slides' of the/saw frame extending through said slots and fixed to the ends of. the piston tion and including hollow vertical side members and hollow upper and'lower cross members 0011- ne'cted-to the side members, the lower cross them, her having guide grooves onits underside slidably int'erfitt'ed with the guiding rails on the basefa sawxffam'e supported onthe vertical members 6f 13' the feed frame for vertical' reciprocation,;gand means for reciprocating the feed frame and comprising afluid pressure motor contained in the hollow base and including a cylinder fixed to the lower cross member of the feed frame, a piston in said cylinder, and apiston rod connected to thepiston projecting exteriorly of the cylinder and anchored to the base. l v Y A metal sawing machine comprising alreciprocatingsaw frame, a-saw blade, means for anchoring one end of the saw blade to the saw;

frame, a bar-like saw gripsecured to the other end of the saw blade and slidably interfitted with the sawframe, a rack on said sawgrip, and a Worm rotatably mounted on the saw frame and meshed-with the rack whereby when theworm is turned in one direction the saw blade is placed under tension. 1 p

6. A metal sawing machine comprising a reciprocating saw frame, a saw blade, means for anchoring one end of the saw blade to the saw frame, a bar-like saw; grip secured to the other end of the saw blade and slidably interfitted with the saw frame, a rack on said saw grip, a Worm rotatably mounted on the saw frame and meshed with therack whereby when theworm is turned in one direction the saw blade is placed under tension, a tool engaging stud, and a slip clutch interconnecting the stud and worm to provide for rotative adjustment of the worm while preventing the placing of an excessive tension on the saw blade. v 1

7. In a metal sawing machine the combination withareciprocating saw frame and a saw blade, of a backing plate engageable with the saw blade, said backing plate having thickened ends formed with elongatedslots, an anchor for one end, of the plate including a, bar-likemember fastened to the saw frameand having an undercut hook fixed thereto and engaged in the slot of the ad- 'jacent end of the backing plate, an adjustable anchor for the other end of the backing plate comprising a bar provided with a hookengaged in the slot in the adjacent end of the backing plate, said slots being longer than the hooks to permit the backing plate to move toward and away fromthe sawblade, a rack on the adjustable; anchor, aworm rotatably mounted on the saw frame and meshing with the rack, and means for shifting the backing plate toward andaway. from the saw blade. r

8. In a metal sawing machine, the combination with a reciprocating saw frame and a saw blade, of a backing plate engageable with the saw blade, means for anchoring one end of the backing plate; to the saw frame, a rack connected to theother end of the backing plate and slidably interfitted with the saw frame, and a worm rotatably supported on the saw frame and meshed with the rack whereby upon rotation of the rack in one direction the backing plate ;Will be placed under tension and held taut in the saw frame. f 9. In a metal sawing machine, the combination with a reciprocating, saw frame and a saw blade, of a backing plateengageable with the saw blade, means for anchoring one end ofthe backing plate to the saw frame, a rack connected to the other end ofthe backing plate and slidably interfitted with the saw frame, a worm rotatably supported on the saw frame and meshed with the rack; whereby upon rotation of the rack in one direction thebacking plate will. be placedunder tension and held taut in the saw frame, a tool engaging stud, and a slip clutch interconnecting the stud andthe worm to provide for. rotative adjustment 14 of the worm while'preventing the placing of an excessive tension on the backing plate; I

:10, Ina metal sawing machine, the combina'-. tion with a reciprocating saw frameand a saw blade, of abacking plate engageable with the saw b1a de, means for stretchingthe backingwplate and holding it taut in the sawframe :while constrain; ing it to, bodily movement toward and away from the saw blade, a pair of clips fixed to the backing, plate, an adjusting block cooperable with each clip, an adjustingshaft for each block, each ad-. justing shaft having an eccentric pin operatively interfitted with its blocks, and means for-rotativea ly adjusting said shafts and releasably securing, them in adjusted position. v a

11. A'rnetal sawing machine comprisinga sta l tionary frame, a feed frame interfitted with guiding ways on the stationary frame for horizontal reciprocatory movement with respect thereto, said: feed frame having opposed vertical side members cross connected at their upper and lower-ends, a vertical guide rail fixed to the inside of eachside member, said guide rails having confronting, .ver tically extending V-shaped guide grooves, a-saw frame having vertical side members-crosscon nected at their upper and lower ends, said, side members of the saw frame beingprovidedfwith. V-shaped slides slidably inter-fitted with theguide grooves of said rails, a sawblade carried by the; saw frame, means for reciprocating the ;feed frame, and means for reciprocating the saw frame.

12. A duplex metal sawing machine comprising a stationary frame," a pair of four-sided feed frames supported ion the stationary frame'for. horizontal movement with respect thereto, a four-: sided saw frame supported on each of said frames for vertical motion relative thereto, saidusaw frames having portions offset outwardly from thecutting plane and having portions lyingcloselyadjacent the cutting plane, saws fixed to the portions'of the saw frames lying closely adjacent the cutting plane, said saws operating in a common cutting-plane and being oppositely-disposed with: their saw teeth confronting, means for reciproeating the'feedframes and means for recipro-z:

eating the saw frames. j

- 13. A metal sawing machine comprising a sta; tionary frame, a pair of four-sided. feed frames interfitted with guiding ways on the stationary frame for horizontal movement with respect thereto, a four-sided saw frame interfitted-with guidin Ways on each of said feed frames for vertical movement with respect thereto, said saw frames having portions offset outwardlyfrom' the;; cutting plane and having portions lying closely adjacent the cutting plane, confronting saws fixed to the portions of the sawframes lying closely adjacent the cutting plane and operating in said'cutting plane, means for reciprocating the feed frames, means for reciprocating the" saw frames, and control devices operated insynchronism with the motion of the saw; frames for causing the saw frames to simultaneously partake first of sawing strokes and then of return strokes and for causing the feed frames to" feed the saws into the work on each'sawing stroke and then retract them a limited distance on each return stroke. 7 1

14. A metal sawing machine comprising a stationary frame, a pair of feed frames interfitted with guide ways on the stationary frame'forhorizontal reciprocatory motion with respect thereto, a saw frame interfitted with guiding Ways on each of said feed frames for verticalreciprocatory motion with respect thereto, a

mounted on the feed frame and carried thereby, valves for distributing the flow of fluid pressure from the source to the several motors, a valve actuated by the saw frame to control the supply of fluid pressure to the distributing valves whereby movement of the feed frame feeds the saw into the work on the cutting stroke thereof and then retracts the feed frame whereby the saw is moved away from the work during the noncutting stroke thereof, and a valve electro-magnetically movable into position to by-pass the distributing valves to cause withdrawal of the feed frame and the saw entirely away from the work.

22. In a metal sawing machine, a base having guideways thereon and having a hollow portion, a feed frame guided on the base ways for reciprocation relative to the base, the feed frame having hollow portions and having guideways formed thereon, a fluid pressure motor mounted in the hollow portion of the base and interconnecting the base and the feed frame for reciprocating the frame relative to the base, a saw frame guided on the feed frame ways for reciprocation relative to the feed frame, the fluid pressure motors mounted in the feed frame hollow portions and interconnected with the saw frame for reciprocation thereof relative to the feed frame.

23. In a metal sawing machine, a base having a hollow portion and having guideways thereon, a feed frame guided on the ways on the base for reciprocation relative to the base, the feed frame having hollow portions and having guideways formed thereon, a fluid pressure motor comprising' a cylinder fixed in the hollow portion of the base and a piston movable in the cylinder and connected with the feed frame for reciprocation thereof relative to the base, a saw frame guided on the feed frame ways for reciprocation relative thereto, and fluid pressure motors mounted in the feed frame hollow portions and connected with the saw frame for reciprocation thereof relative to the feed frame.

ADAM ZISKA. 

